Significant findings of the prehistoric era were discovered in Kos.
From the 3rd to the 17th of June 1922 Alesandro Della Sefa, director of the Italian Archaeological school in Athens, with Doro Levi dug up the cave of Aspri Petra on the mountain Zini in Kefalos.
The cave of Aspr Petra is one of the most important findings of the prehistoric era. According to those findings the cave is chronologically placed to the early Neolithic era and the very early Bronze age (3000 BC). Human fossils, Neolithic shards and other findings were found.
The important of that cave must be pointed out. It used to be a place of worship. There have been discovered findings not only of the prehistoric era but also of the later times, till the Roman era. It is considered to be one of the oldest monuments of the island.
According to the earthen pots that were found in the cave, the worship of the Gods went on even until the Roman era.